Screw-propeller



(No Model.)

3.1mm. SCREW PROPELLER Patented May 2, 1882.

- Inventor:

l Wlwsses. 7mm hfmmdA by Attorney.

' described.

` the rear portion of which is bored out hollow UNITED STATES PATENT OFFICE.

RICHARD UREN, OF HOUGHTON, MICHIGAN.

SCREW-'PROPELLER SPECIFICATION formingpart of Letters Patent No. 257,416, dated May 2, 1882.

Application filed July 21, 1881. (No model.)

Tocll whom t may concern:

Be it known that I, RICHARD UEEN, of Houghton, in the county of Houghton and State of Michigan, have invented a new and useful Improvement in Screw-Propellers, of which'the following, taken in connection with the accompanying drawings, is a specification.

My invention relates to the construction of screw-propellers for steam-vessels and their supporting-shafts, and has for its object a reduction of the resistance to the revolutions of the propeller due to the friction of the water upon the surface ofthe propeller-blades; and it consists in forming the blades of the propeller hollow, with one or more openings at or near their forward edges, so formed and -arranged that the exterior month ofsaid opening or openings shall be in close proximity to the exterior surface of the blade along its front radial edge and face toward the rear radial edge of said blade.

It further consists in the combination of a propeller constructed as above set forth and a hollow supporting and operating shaft, through which air may be forced to the interior of the propeller-blades, as will be further Figure l of the accompanying drawings is an end elevation of a screw-propeller embodying my invention. Fig. 2 is a sectional elevation, the cutting-plane being on line .fr .r on Fig. l; and Fig. 3 is a section through one of the blades on line y y on Fig. l.

A is the propeller, provided with blades c a., made hollow, as shown, with openings b in their front edges, which openings are covered by the overlapping shields or hoods c c, but not closed thereby, said shields or hoods c c serving to form an extension and a division of the' passage from the interior of the blade, and to turn the two divisions backward, so that the mouths ofthe openings b are toward the back edge of the blade. The shield or hood c is riveted to the propeller-blade through and through, thimbles or washers being placed between said hood and the blade and between the two parts of the blade, as shown in Fig. 3. p

B is the rear section ot' the propeller-shaft,

and has inserted in its rear end the screw-plug d. Nearits rear end are drilled the two radial holes e e, in positions to connect with the chambers f f in the arms a a of the propeller A with the central or longitudinal passage, g, of the shaft l B,theinnerendofwhicheommunicatesthrough the radial holes h with the an nular chamber i in the stationary bearing C, which is connected by the pipej with an air-pump. (Not shown.) The bearing (l is provided with two stufing-I boxes, one upon each side ofthe chamber i, to prevent leakage of air around the shaft B.

D is the stern-post of the vessel, provided with a suitable bearing for the shaft B and a suitable stufng-box, lr, to prevent water entering the vessel.

i The operation of my invention is as follows: Any well-known air force-pump being connected to the pipe]- and set in operation, air will be forced into the 'chamber z' through the holes h, passage g, holes c, and the chambers f fin the arms ct a of the propeller A, and escaping through the openings b in the front edges ot' the blades a a is dellected by the hoods ce and turned in two divisions around the edges of the blades, and is discharged toward the rear edges of said blades, between the surface of said blades and the surrounding walter, thus causing a ihn of air to be interposed betwcen the blade and water and materially reducing the friction of the water upon the blades of the propeller and causing a great saving in the power required to revolve the propeller.

Vhat I claim as new, and desire to secure by Letters Patent of the United States, is-

l. A screwpropeller having hollow blades, each provided with one or more orifices in close proximity toits front radial edge and opening toward the rearradial edge of said blade, substantially as described.

2. A screw-propeller having hollow blades, each provided with two or more orifices in close proximity to its front radial edge and opening towardthe rear radial edge of saidA blade, one or more upon each side ot' said blade, substantially as described.

3. The combination ol' the propeller A, having hollow arms a. a., each provided with one or more openings, b I), the hoods' c c, and mechanism for forcing air through the hollow arms (t aand the orifices b b, substantially as'andl for the purposes described.

Executed atBoston,Massachusetts,this 11th day of July, A. D. 1881.

A RICHARD UREN. Witnesses: E. A. HEMMENWAY, WALTER E. LOMBARD. 

